Legend tells how long ago bio mechanical being from space attacked earth. Men called them Flutter Drones. It recounts how they hunted man to feed upon his flesh. The struggle was long and hard. Finally they were driven back into space. The Earth was left cityless. Each destroyed by air mines launched by the larger Master Drone leader.
Earths survivors built one massive city and installed a defence system against the drones. A network of towers each with a scanner designed to seek and destroy drone packs with a minimum risk to human life.
- Scanner 13 (Zipped .CAS file)